Experimental mirror energy differences (MED) for nuclei lying in the middle and the second part of the 1
f
7/2
shell are compared with shell model calculations in the 1
f
7/2
and in the full
pf
...configuration spaces, as well as with cranked shell model calculations. MED plots are fully consistent with the description which emerges from the interpretation of SM calculations:
i.e.
the band-crossing of the gs band with high-
K
bands in
A
= 51 and 50 mirror pairs, as well as the seniority-3 quasi band-termination at
in
A
= 49 . Rotational alignment effects are excluded, contrarily to what even recently proposed. Some inconsistencies, as well as definition improprieties, are pointed out in the topical literature.
Gamma rays from the N = Z-2 nucleus (50)Fe have been observed, establishing the rotational ground state band up to the state J(pi) = 11+ at 6.994 MeV excitation energy. The experimental Coulomb ...energy differences, obtained by comparison with the isobaric analog states in its mirror (50)Cr, confirm the qualitative interpretation of the backbending patterns in terms of successive alignments of proton and neutron pairs. A quantitative agreement with experiment has been achieved by exact shell model calculations, incorporating the differences in radii along the yrast bands, and properly renormalizing the Coulomb matrix elements in the pf model space.
The spectroscopic quadrupole moments of the 11− and 12+ isomers in 192,194Pb, described by the 3s1/2−21h9/21i13/2 intruder two-proton and 1i13/22 two-quasineutron configurations, respectively, have ...been determined by the method of time-differential observation of the γ-ray perturbed angular distribution. The derived values are |Qs|(12+,192Pb)=0.32(4) eb, |Qs|(11−,192Pb)=2.9(3) eb and |Qs|(11−,194Pb)=3.6(4) eb. The 8+ 2304 keV and 9− 2514 keV states in 192Pb have been identified as isomers, with half-lives of 3.9(3) and 3.3(2) ns, respectively. The experimental spectroscopic quadrupole moments for the 11− and 12+ isomers in neutron deficient Pb nuclei have been described in the framework of the pairing plus quadrupole model. The intrinsic quadrupole moments and deformation of the 11− isomers are compared with the predictions of mean-field and interacting boson models.
A new analysis procedure is proposed for the Doppler Shift Attenuation Method in γ–γ coincidences, which allows the determination of the lifetime of nuclear levels without the influence of ...sidefeeding. The procedure consists in taking as the gate, the non Doppler shifted portion of a γ-transition from the level being studied and in describing the suppression effect in the line shape of a coincident transition above it, with respect to that obtained with a gate including the whole line shape. The procedure, named Narrow Gate on Transitions Below (NGTB), can be efficiently employed using the current large γ-multiarrays.
This paper presents the results of the geoarchaeological study of a medieval motte known in historical documents as “Castrum Popilii” (Poviglio, Northern Italy). The Castrum Popilii motte, for its ...particular environmental characteristics, represents an exceptional case study for the Early Medieval Age in Po Valley. In 1989 an archaeological rescue excavation revealed an exceptionally well-preserved stratigraphic sequence at the northern side of the Santo Stefano church. The study of the archaeological materials and thin soil sections collected during this campaign, integrated with geoarchaeological observations, allowed the reconstruction of the natural and anthropogenic processes involved in the formation of the Santo Stefano di Poviglio stratigraphy sequence. The area also referred to as “Santo Stefano di Poviglio”, exposed the eastern limit of the medieval motte, characterizes by a sequence of occupation deposits, living floors, and wooden structural remains dated between the late 9th and the 11th centuries AD.
The micromorphological study of this archaeological site led to developing a new hypothesis about the use of lime-based plaster in the construction of domestic living floors in a rural early medieval village in Central Po Plain. The sealing of the sequence due to the construction of a stone stronghold in the 15th century, combined with waterlogging, preserved the deposit from reworking by bioturbation and later human activities. On the other hand, water stagnation influenced a series of post-depositional migration and accumulation of iron–manganese and phosphatic features. The geoarchaeological tools applied in this study allowed to maximize the data collected in a rescue situation in 1989 highlighting new information about the genesis and development of Castrum Popilii medieval motte.
•First micromorphological research conducted on an Early Medieval Motte in Northern Italy•Exceptional case of well-preserved Medieval stratigraphic sequence in Central Po Plain•Distinguish archaeological stratigraphic units through formation processes•Identification of living floors and occupational deposits related to a timber-framed house•The analyses performed highlighted new information about the use of impure lime-based plaster in an Early Medieval village
Experimental mirror energy differences along yrast bands of nuclei lying in the middle and the second part of 1f (7/2) shell are compared with shell model calculations in lie 1f (7/2) and in the full ...p f configuration spaces, as well as with CSM calculations. MED plots are consistent with the description which emerges from the interpretation of SM calculations: i.e. the band crossing of the gs band with high-K bands in A=51 mirror pairs, as well as the seniority-3 quasi band-termination at I(pi)=19/2-in A=49. Rotational alignment effects are excluded, contrarily to what even recently proposed. Some inconsistencies are pointed out in the topical literature.
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